1. Technical Field
The present invention relates to a light source device and to an image display device, a monitor device, and a lighting device comprising the light source device.
2. Related Art
Image display devices are in use wherein images are displayed by illuminating, with an illumination beam from a light source device, spatial optical modulator devices such as light valves and digital mirror devices (DMDs). The image display devices use a laser beam source that emits laser beams, for example, as a light source.
The laser beam source produces heat through its operation, where the temperature of the device itself increases with the time of operation. In order to prevent a reduction in the service life of the laser beam source device due to increased temperatures, image display devices are provided with, for example, cooling devices for cooling the laser beam sources.
However, there are concerns that the temperature of the laser beam source may exceed the tolerable temperature due to a failure in the cooling device, for example, or due to use of the image display device in an environment exceeding the tolerable temperature at which stable operation of the laser beam source is possible. When the temperature of the laser beam source exceeds the tolerable temperature, then there is the problem that the output power of the laser beam source falls quickly when compared to the case of stable operation. Furthermore, the higher the operating temperature of the laser beam source, the shorter the period which the laser beam source is able to emit a stable laser beam, or in other words, the shorter the service life of the laser beam source.
The issue described above is not an issue that is limited to image display devices that use laser beam source devices, but rather is an issue that can occur also in monitor devices and lighting devices that use laser beam source devices.